YAML / JSON / TOML Converter

Convert between YAML, JSON, and TOML formats instantly in your browser. Paste config files, API responses, or data structures and get the equivalent in another format.

100% client-side. Your data never leaves your browser.

Converters & Examples

CSV to JSON Converter: Tabular Data Transformer

Convert CSV data to JSON array of objects. First row becomes keys. Handles quoted fields, commas in values, and empty cells.

 JSON to YAML Converter: Online Transformer

Convert JSON to YAML format instantly. Handles nested objects, arrays, multiline strings, and preserves data types.

 YAML to JSON Converter: Config Format Translator

Convert YAML configuration files to JSON. Resolves anchors, validates syntax, and produces valid JSON output.

Related Tools

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JSON Formatter + Tree Viewer

Paste JSON to pretty-print, minify, or validate it with syntax highlighting and an interactive tree view. Real time error detection with line numbers.

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SQL / CSS / HTML Formatter

Format and minify SQL queries, CSS stylesheets, and HTML markup with syntax highlighting. Indent, beautify, or compress code in your browser.

YAML / JSON / TOML Converter

Convert data between YAML, JSON, and TOML without installing CLI tools or writing a script. Paste your configuration file, API response, or data structure, choose a target format, and get the converted output instantly. Everything runs in your browser.

How to Use

  1. Select the input format using the From buttons (JSON, YAML, or TOML), or click Detect to identify the format automatically
  2. Select the target format using the To buttons
  3. Paste or type your data in the input panel. The output updates as you type
  4. Adjust indentation with the indent selector (2 or 4 spaces) for JSON and YAML output
  5. Click Copy to grab the result, or use Swap to reverse the conversion direction

Why Three Formats Exist

JSON became the universal data interchange format because it maps directly to the data structures in most programming languages: objects, arrays, strings, numbers, booleans, and null. Its rigidity (no comments, strict quoting, mandatory commas) is a feature for machine parsing and a pain point for human editing.

YAML was created as a human friendly data serialization language. Indentation based nesting, bare strings, comments, and multiline values make it natural for configuration files. That flexibility comes with complexity: YAML has type coercion rules that surprise experienced developers (the Norway problem, where the country code NO parses as boolean false), and whitespace sensitivity means a single misplaced space can silently change your data structure.

TOML was explicitly designed to be a minimal configuration file format that is easy to read because of its obvious semantics. It uses INI file style section headers with strict typing. TOML works well for flat to moderately nested configs but becomes verbose for deeply nested data because every level needs a full dotted key path or table header.

Understanding the tradeoffs helps you pick the right format: JSON for APIs and serialization, YAML for complex DevOps configurations, TOML for application settings.

Need to format or validate JSON before converting? Use the JSON Formatter. Working with SQL or CSS configs? The Code Formatter handles those languages.